Pendulum



A. L. SOHM. PENDULUM. APPLICATION man MAY5,1919.

Patented Oct. 25, 1921.

UNITED STATES .PATENT OFFICE.

ALFRED L. SOM, OFCHICAGO, ILLINOIS, ASSIGNOR TO SOI-H41 ELECTRIC COMPANY, OF

CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

' PENDULUM.

Specification of Letters Patent.

Patented Oct. 25, 1921.

Application led May 5, 1919. Serial No. 294,783.

To all whom t may concern.'

Be it known that I, ALFRED L. SOHM, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented acertain new and useful Improvement in Pendulums, of which the following'is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forminga part of this specification.

My invention relates to pendulums. Y

' More particularly my invention relates to pendulums such as are employed in connection with clocks and the like for properly regulating the escapement thereof.

' The usual clock pendulum generally comprises a wood or metallic pendulum rod suspended so as to fmov'e freely about its point 'of suspension and having a suitable weighted member or bob attached to its lowerend. As well understood Aby those skilled in the art, 'the usual clock is nothing more than a pendulum with suitable means for registering the number of oscillations thereof and means such asa spring wherein suiiicient energy is periodically .stored to counteract the retarding effects of friction and the resistance of air.

y,I have observed that in regulating clocks in order to compensate for ltemperature changes and the like, the usual and most convenient manner of making such adjust- Y ment is by adjusting the vlength of the pendulum, thatv is by .either shortening or lengthening the same. It is therefore desirable to have the weighted member or bob adjustably mounted on the pendulum rod. Attempts to meet this requirement have resulted in numerous complex devices.

My invention aims to provide a pendulum of simple and inexpensive construction which is capable of quick and easy assembly, may be quickly and easily adjusted and is effective in operation.

In accordance with the teachings of my invention I have provided a pendulum which may be quickly assembled or readily adjusted without the use of a wrench, pliers, screwdriver or the like, the weighted member or bob being effectively held at all times against displacement regardless of its position on the pendulum rod. V

Other aims of my invention will appear from th-e following detailed description,

taken with an inspection of the accompanying drawings, in which- Figure l'is a rear elevational view of a.

of either1 wood or metal, preferably of wood in order to approach'asnearly as possible the simple pendulum, is adapted to be suspended'as, for' instance, from the verge or escapement shaft of the clock. In this case the escapement shaft of the clock is adapted for, oscillating freely with the pendulum.

The rear face 3 of the bob 2 is provided with a groove or channel which extends diametrically thereacross, as shown in Figs. 1 and 2. The groove or channel 4 is adapted for receiving the lower end of the pendulum rod l, the opposing shoulders 5 and 6 of the groove serving to maintain the p endulum rod l vertically alined therein. A strap 7, preferably formed integral with the bob 2, although it. may be a .separate piece suitably bolted to the bob if so desired, is bridged across the groove or channel l and serves together Vwith a suitable spring bridge 8 to retain the bob securely in place lowed between the strap 7 and the pendulum rod l for the reception of the bridged spring retaining member 8.

The center of the bridged spring retaining member 8 is provided with a depressed portion 9 for receiving the strap 7 when the bridged spring is sprung thereunder. The opposite ends of the bridged spring retaining member 8 are adapted for engaging the pendulum rod'l at the points 10 and11 respectively, the extremerends being bent upwardly from these points of engagement Aso that the bridged spring 8 may be moved freely along the pendulum' rod when so desired. The opposite ends of the bridged spring retaining member 8 are inclined up; wardly from its points of engagement with the pendulum rod to the depressed portion V9, the height of the bridge thus formed being such that it can be sprung under the strap 7, the opposing shoulders 12 and 13 formed bythe depressionY 9 engagingthe opposite edges of the strap 7 and thereby preventing displacement of the bob 2. lVhen'V the bridged spring retaining member 8- is sprung into position under the strap i7 as Y shown in Fig. 2 it will-engage the pendulum rod 1 at the points 10 and 11 respectively and' thereby create sufficient .friction between the pendulum rod and the bottom of v the grooveor channel 4to prevent any but intentional movement of the bob 2 along the 'shaft 1.

If it is desired to adjust the length ofthe lpendulumin'order to regulate the clock the bob 2 ismoved either upwardlynor down- V wardly along the pendulum rod 1 against `the' 'frictional engagement betweenl the rod Y pendulum rod. For making vfine adjust- 1 andthe bottom of the groove 4, thisv frictional engagement not being suiiicient to prevent such movement, althoughitis suliicient to, prevent accidental slipping or otherun intentional movement of the bob along the rod 1. The bob 2 is moved either upwardly or downwardly along the pendulum rod 1, accordingly as'to whether the speed of the clock is to be increasedvor decreased, as well understood by those skilled in the art. Upon moving the bob 2 to the desired position on the pendulumrod 1 andv then releasing the bob it will beeffectively held in place by the bridged spring retaining memberS, which upon being Vsprung beneath the strap 7 is constantly-'in frictional engagement with the ments itiis apparent thatthe pendulum rod lcould be provided with a suitable scale, a pointer being provided on the bob 2 for readily indicatingl the amount of movement of the bobwhenthe same is adjusted.

Itwill now be apparent that I have provided a pendulum of extremely simple and {ception ofvsaid pendulum rod, abridge member extending across said groove and a spring retaining member yieldingly engaged lbetweenthependulum rod and said bridge memberrfor preventingY free movement of said bob. Y

' 2.V In combination, a pendulum -rod,a bob Y having a groove in one of the faces thereof for the reception of sa1dfpendulum'rod,`a

bridge member extending across said groove a spring retaining member arranged in said groove between the pendulum rod and said bridge member, said spring retaining member having af-depressed -portion therein for cooperating with said bridge member, to prevent unintentional displacement of the spring. i

3. In combination, a pendulum rod,a bob,

and a spring retaining member sprung between the pendulum rod and thebob to prevent freemovement oftheV bob, Vsaid spring retaining member being held against displacement by its yielding: engagementV between the pendulumrod andthe bob.

In witness whereof, I hereunto subscribe my namethis v28th.V day of March A. D. 1919.

l :ALFRED L; soHM. 

